Patent · US Expired

Fault tolerant memory system which utilizes data from a shadow memory device upon the detection of erroneous data in a main memory device

US5619642A · kind A · utility

86Cited by
13References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1994
Grant dateApr 8, 1997
Priority date
Expiry dateDec 23, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2211/1009
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A fault tolerant memory system is disclosed which includes a main memory device, storing data and an associated error detecting code, and a shadow memory device, storing data corresponding to the data stored in the main memory. A multiplexer, selectively couples data from either the main memory device or the shadow memory device to an output terminal in response to a control signal. A controller reads the data and associated error detecting code from the main memory device and the corresponding data from the shadow memory device, and generates the multiplexer control signal such that the multiplexer couples data from the shadow memory device to the output terminal if the data from the main memory device is not the same as the data from the shadow memory device and the error detecting code indicate an error in the data from the main memory device, and otherwise couples the data from the main memory device to the output terminal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.